IP boutique Wallenstein & Wagner is disintegrating, with specialist and national firms rushing to benefit.

The Chicago firm’s problems are understood to have been sparked by an unconfirmed contract dispute. However, it has been struggling since entering a costly lease agreement three years ago for its South Wacker Drive premises.

Former partner James Muraff explained that the lease had made the firm “less competitive compensation-wise”.

Both McDermott Will & Emery and IP firm Banner & Witcoff have moved quickly to plunder Wallenstein. Eight lawyers joined McDermott last week, while five joined Banner earlier this month.

In addition, three lawyers joined Chicago firm Schwartz Cooper, while Muraff moved across to Neal Gerber & Eisenberg as senior counsel.

Wallenstein was unavailable for comment.